Hi all you knowledgeable, helpful people. I've recently bought my first flat (ground floor) & am dismayed to find it suffers from condensation/mould. The problem is worst in the bedroom (particularly the built in wardrobe) which has 2 outside walls 5.25m (north facing) & 2.7m (east facing). The room is heated by 1 x 3.4Kw storage heater (positioned on an internal wall), there is a recently installed double glazed window without a trickle vent and no other vetilation in the room. - There is however a duct running from the bathroom along the top of the north facing wall. From searching this site I reckon I need to; a) move 3.4Kw heater to north (longest) wall, b) fit another heater (1.7Kw???) to east (shorter) wall & c) increase ventilation. Can I do this by fitting louvred slots in the afore mentioned ducting - If so how large should they be? - Any advice gratefully received.